public override object VisitExternalFunctionDefinition([NotNull] functionalParser.ExternalFunctionDefinitionContext context)
{
var predicate = ((string, string[], Ty))Visit(context.predicate());
if (predicate.Item2.Length != 0)
{
ErrorReporter.ErrorFL("An external function cannot be generic", FileAndLine(context));
}
FunctionType functionPredicate;
if (predicate.Item3.Type.Is <FunctionType>())
{
functionPredicate = predicate.Item3.Type.As <FunctionType>();
}
else
{
// If the predicate is not a function type make it into one (e.g. main :: Int)
functionPredicate = new FunctionType(new Ty[] { predicate.Item3 });
}
return(new FunctionNode(predicate.Item1, functionPredicate, FileAndLine(context)));
}
/// <summary>
/// Visit a parse tree produced by the <c>ExternalFunctionDefinition</c>
/// labeled alternative in <see cref="functionalParser.definition"/>.
/// <para>
/// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/>
/// on <paramref name="context"/>.
/// </para>
/// </summary>
/// <param name="context">The parse tree.</param>
/// <return>The visitor result.</return>
public virtual Result VisitExternalFunctionDefinition([NotNull] functionalParser.ExternalFunctionDefinitionContext context)
{
return(VisitChildren(context));
}
